Conventional brushless motors typically include a casing for containing a stator body and a rotor with driving shaft, an exit cap with an outlet for said driving shaft and a closure cap, which is opposite said exit cap, which supports an electronic board for controlling the brushless motor and comprises an output for power cables.
Currently, the need is felt increasingly to have a brushless motor which is dimensionally compact, both axially and radially, and in which at the same time the electronic board is in a protected position that is easily accessible in case of repair or replacement.
In a known type of brushless motor, the electronic control board, usually an encoder, is arranged outside the cap, inside a protective hood that is extended externally to said cap in an axial direction.
This solution, though having the merit of allowing easy adjustment of the encoder, which is easily accessible by removing the hood, which is external to the cap, without having to disassemble the cap from the brushless motor proper, suffers the drawback that it increases significantly the axial space occupations of the motor and determines a single output for cables which is radial with respect to the motor, an arrangement that is a limitation for applications requiring a reduced radial space occupation.
In a further, different, type of brushless motor, in order to reduce axial space occupations the encoder is arranged inside the cap, fixed to an annular portion that extends from said cap and is coaxial to the rotation axis of the driving shaft, in a region located further inward than the bearings for the driving shaft on the side of said cap.
This arrangement of the encoder, while making the motor more compact axially, makes it impossible to access the encoder except by disassembling the cap, and this entails the loss of the protection degree and makes the operation of synchronization between the signal of the encoder and the rotor magnetic field more difficult; as is known, this synchronization is necessary for the operation of a brushless motor.